Apache2 conf file with SSL causes ERR_CONNECTION_REFUSED - apache

Question

I am trying to configure my SSL certificate on a Ubuntu 15.10 box. I have installed the certificate files and the private key in the required directory:
SSLCertificateFile /etc/apache2/ssl-certs/pts.crt
SSLCertificateKeyFile /etc/apache2/ssl-certs/msk.key
SSLCertificateChainFile /etc/apache2/ssl-certs/intermediate.crt
When I do sudo service apache2 restart I am then prompted to Enter passphrase for SSL/TLS keys for www.mydomain.com:443 (RSA): ******** and since this process reports back with no errors, I am assuming that I have at least installed the certificates and private key correctly, otherwise I would have expected an error at this stage.
My problem is that I receive ERR_CONNECTION_REFUSED when trying to load the site.
Here is my backup copy of the VirtualHost entry for the SSL site that I am using. Are there any obvious problems with this file?
I should also add that when I use this configuration, not only does the intended site fail to load, but it also causes all other sites for this apache2 box to fail to load also. Any ideas?
`<VirtualHost *:80>
ServerName mydomain.com
ServerAlias www.mydomain.com
ServerAdmin daniel#mydomain.com
RewriteEngine On
RewriteCond %{HTTPS} !on
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}
</VirtualHost>
<VirtualHost 172.30.30.21:443>
ServerName www.mydomain.com
ServerAlias mydomain.com
ServerAdmin me#mydomain.com
SSLEngine on
SSLProtocol all
SSLCertificateFile /etc/apache2/ssl-certs/pts.crt
SSLCertificateKeyFile /etc/apache2/ssl-certs/msk.key
SSLCertificateChainFile /etc/apache2/ssl-certs/intermediate.crt
DocumentRoot /home/apts/Dropbox/mydomain.com/
<Directory /home/apts/Dropbox/mydomain.com/>
<IfModule mod_rewrite.c>
<IfModule mod_ssl.c>
# <Location /squirrelmail>
RewriteEngine on
RewriteCond %{HTTPS} !^on$ [NC]
RewriteRule . https://%{HTTP_HOST}%{REQUEST_URI} [L]
# </Location>
</IfModule>
</IfModule>
SSLOptions +StrictRequire
Options +FollowSymLinks -Indexes +MultiViews
AllowOverride All
Order allow,deny
allow from all
</Directory>
SSLProtocol -all +TLSv1 +SSLv3
SSLCipherSuite HIGH:MEDIUM:!aNULL:+SHA1:+MD5:+HIGH:+MEDIUM
SSLVerifyClient none
SSLProxyEngine off
</VirtualHost>`